An electric traction vehicle is a vehicle that uses electricity in some form or another to provide all or part of the propulsion of the vehicle. This electricity can come from a variety of sources, such as stored energy devices relying on chemical conversions (batteries) to create electrical energy, stored energy devices relying on stored electrical charge (capacitors), stored energy devices relying on mechanical stored energy (e.g., flywheels, pressure accumulators), and energy conversion products. In a typical conventional electric traction vehicle, a prime mover, such as a diesel engine, is used to drive an electric generator or alternator which supplies electric current to one or more traction motors. The traction motors typically are coupled to wheel sets on the vehicle. A typical vehicle that utilizes this type of electric traction is a railroad locomotive. In some conventional electric traction vehicles, stored energy is used to provide the main power which provides the electrical current to one or a plurality of traction motors. A typical vehicle that utilizes this type of electric traction is a golf cart or battery powered electric car. In some conventional electric traction vehicles, having more than one source of energy is desirable. By having more than one source of energy, some optimizations in the design can allow for more efficient power production, thus allowing power to be used from different sources to come up with a more efficient system for traction. These types of vehicles are commonly referred to as hybrid electric vehicles (HEV). Series and Parallel HEV system designs are what is usually encountered.
Electrical devices for use with electric traction vehicles, and more particularly energy storage units for use with electric traction vehicles, such as ultracapacitor storage units, may typically store large amounts of electrical energy during use on the electric traction vehicle. Similarly, electrical energy storage units that are not mounted to an electric traction vehicle may also contain large amounts of stored electrical energy. The stored electrical energy typically needs to be isolated or dissipated from the electrical energy storage unit when maintenance is to be performed on the electric traction vehicle or before the electrical energy storage unit is handled in order to avoid electrocution of maintenance personnel. The amount of stored electrical energy may be large enough to create an electrocution hazard to a person handling or working within reach of the electrical energy storage unit if that person is unaware of the presence of the stored electrical energy. Thus, it would be beneficial to provide a status indicator for use with electrical traction vehicles in order to provide an indication of the presence of electrical energy, such as electrical energy stored in an energy storage device. It would be further beneficial to provide the status indicator with the electrical energy storage device as a single integral unit.